1. Field of the Invention
The present invention relates to ski boots and has specific reference to a ski boot comprising a shell of semi-rigid material consisting of a lower portion including the sole and surrounding the skier's foot and of a shaft made of two sections, namely a front quarter and back quarter; and resilient means for counteracting the forward flexion of the front quarter of the shaft, and foot holding means inside the shell.
A ski boot of this type, commonly referred to as a rear-entry boot due to the possibility of tilting the rear quarter of the shaft backwards, is disclosed for example in U.S. Pat. No. 4,160,332. This boot consists of a rigid shell surrounding the skier's foot and has fixed volumetric dimensions in contrast to the so-called variable-volume boot in which the upper can be tightened for properly fitting on the foot. Since the volume of this shell portion cannot be reduced, the foot is held by means of an internal device comprising on the one hand a bearing plate having the configuration of the insteps and secured to the vamp or to the inner slipper, and on the other hand cable means permitting of exerting a tractive effort in a diagonal direction on said bearing plate towards the heel, and thus properly nest the skier's heel in the heel cavity of the boot. Under these conditions, the proper fitting of the skier's foot depends almost completely on the proper fitting of the heel in its cavity. The front portion of the foot too is obviously not held in the case of a narrow foot, so that the play between the foot and the inner space of the boot may become excessive and render ski practice more difficult.
Now this problem is eliminated in ski boots of which the vamp is provided with flaps adapted to be tightened by means of buckles, but boots of this type, though very popular before the advent of shell boots, can scarsely prevent the ingress of snow and water.
2. Summary of the Invention
It is the primary object of the present invention to provide a shell-type ski boot having a variable inner volume, that is, the possibility of adapting the inner transverse dimensions of the boot to the foot dimensions and consequently of warranting a satisfactory fit of the foot in the boot.
For this purpose, the ski boot according to the present invention is characterized in that the foot-covering portion of the shell consists on the one hand of at least one pair of opposed flaps attached to the sole and on the other hand of a vamp covering said flaps and the entire front portion of the foot, said flaps comprising means for holding said resilient flexion-counteracting member.
The flaps are tightened around the foot by means of suitable tightening means, consisting for example of a traction cable attached to the end of one flap and passing over the other flap.
In order to obtain a satisfactory fit of the foot, preferably two pairs of flaps, each tightened by separate tightening means so as to provide a two-point tightening system, are provided. When cables are used, the two cables may be tensioned by means of a common, single lever.
It is unnecessary that the flaps surround the foot completely, since the fluid-tightness is provided by the cover. It is thus possible to imprat a relatively high degree of freedom to said flaps so as to facilitate the tightening thereof.
According to a specific form of embodiment of the invention, the vamp is an integral part of the front quarter of the shaft and the projection formed on the front quarter is arrow-headed and adapted to be hooked under tension to the vamp. This arrangement is advantageous in that it permits not only of molding the front quarter of the shaft and the vamp in the open condition, that is, with the arrow-head released from the cover, but also of anchoring the arrow-head to the vamp during the assembly, by bending the front quarter of the shaft.
According to another form of embodiment of the invention, the upper transverse edge of the vamp is covered by the shaft and the resilient member is disposed between the vamp and the shaft, and engages both a projection of said vamp and a projection of said shaft.
Another advantageous feature of the ski boot according to the present invention is that all means for fastening a bearing plate to the shell or to the inner slipper can be dispensed with.